Mechanism for sealing coin insertion slots in time vending machines or the like

ABSTRACT

A mechanism for normally sealing and blocking the coin insertion slot of a parking meter or another coin-operated machine has a mask which is formed with the slot and one side of which is adjacent to two pivotable blocking members which are biased to operative positions wherein they overlie the slot. The other side of the mask supports two reciprocable scanning members which normally extend into the slot and are displaceable by a satisfactory coin to thereby pivot the respective blocking members from operative positions. The scanning members have locking bolts which engage and hold the respective blocking members in operative positions while the scanning members extend into the path of movement of a satisfactory coin into the slot.

Unite States atent 1191 Kaiser et a1.

[4 1 Nov. 11, 1975 Wokiick, Schwenningen, both of Germany [73] Assignee: Kienzle Apparate GmbH, Villingen,

Germany Filed: Nov. 15, 1973 Appl. No: 416,249

[30] Foreign Application Priority Data Rabkin 194/102 Bradley 194/102 Primary Eran1i/1erStan1ey l-l. Tollberg Attorney, Agent, or FirmMichael S. Striker [57] ABSTRACT A mechanism for normally sealing and blocking the coin insertion slot of a parking meter or another coinoperated machine has a mask which is formed with the slot and one side of which is adjacent to two pivotable blocking members which are biased to operative positions wherein they overlie the slot. The other side of the mask supports two reciprocable scanning members which normally extend into the slot and are displaceable by a satisfactory coin to thereby pivot the respective blocking members from operative positions. The scanning members have locking bolts which engage and hold the respective blocking members in operative positions while the scanning members extend into the path of movement of a satisfactory coin into the slot.

35 Claims, 4 Drawing Figures US. Patent Nov. 11,1975 Sheet 1 of2 3,918,566

MECHANISM FOR SEALING COIN INSERTION SLOTS IN TIME VENDING MACHINES OR THE LIKE BACKGROUND OF THE INVENTION The present invention relates to coinor tokenoperated machines in general, and more particularly to improvements in safety mechanisms which admit coins or tokens (hereinafter called coins) into the interior or coin-operated machines to thereby initiate one ore more operations, such as the displacement of a pointer in a parking meter, the closing of one or more switches in a washing machine or dryer, the starting of a motor in a shoe shining machine, and/or others. Still more particularly, the invention relates to improvements in mechanisms which normally seal coin insertion slots in coin-operated vending and like machines.

It is well known that coin-operated time vending machines or other coin-operated machines are favored targets of thieves and vandals. Therefore, such machines are normally provided with means for preventing the introduction of slugs or similar objects which somewhat resemble satisfactory coins or tokens but are worthless to the owner of the coin-operated machine. Satisfactory prevention of thefts of services or commodities is particularly desirable when a large number of coin-operated machines are set up in public places so that they are readily accessible to legitimate users as well as to would-be thieves and vandals. For example, very ingenious devices were designed by thieves to avoid the insertion of valuable coins or proper tokens into parking meters. Since the insertion of a coin or token into the slot of a parking meter results in the purchase of an authorization to use a particular space for a certain interval of time, i.e., not in the purchase of tangible goods, many persons do not consider it a serious offense to manipulate parking meters with a view to avoid the insertion of a valuable coin or the purchase of a specially designed token which can actuate the mechanism in the interior of the meter so that the pointer moves to a position which indicates that the person is entitled to park his or her car in the corresponding parking space. This leads to a surprisingly large nuinber of often involved and quite frequently successful attempts to manipulate parking meters without any cost to the offenders. The owner of parking meters suffers substantial losses not only if the users of.

parking spaces do not pay for the time but also if the users in attempting to use a slug, clog or jam the slots or damage the delicate mechanisms in the parking meters so that the latter cannot accept satisfactory coins or their pointers continue to indicate that proper pay ment for the use of corresponding parking spaces has been made. As a rule, the majority of attempts to trigger the operation of a parking meter by using a slug or the like result in damage to parts or in a total breakdown of the meter.

French Pat. No. 1,592,485 discloses a safety mechanism which is intended to normally block the entry of objects into the slots of coin-operated parking meters and opens only when a coin or token of proper size and shape is being employed by the person who is desirous of purchasing time from the owner of the parking meter. The mechanism of the French patent employs a flap which is biased by springs to overlie the coin insertion slot but can be displaced by pivoting about two mutually inclined axes when a coin of satisfactory size and shape is being used. The shafts which define the two pivot axes are coupled to each other by a rod and one thereof is movable with respect to the other shaft. The flap cooperates with a locking finger which is shifted aside in response to insertion of a satisfactory coin. A drawback of such mechanisms is that the locking finger can be readily displaced from without by a large variety of flat objects or slugs and that the flap is ready to be moved aside by any object which even remotely resembles a satisfactory coin or token. It has been found that the just described mechanism is no match for sophisticated or halfway sophisticated thieves who are about to utilize the parking space without paying therefor. Moreover, the flap takes up considerable space for pivotal movement between open and blocking positions so that the depth of such mechanisms is much greater than warranted by the overall size of a streamlined parking meter. Therefore, the parking meters must be overdimensioned for the express purpose of accommodating the just discussed saftey mechanisms.

SUMMARY OF THE INVENTION Another object of the invention is to provide a safety mechanism for normally obstructing the slots of coinoperated vending and like machines wherein the slot becomes unobstructed only and alone in response to utilization of a satisfactory coin or token and which is much less likely to accept slugs or the like than a conventional mechanism.

A further object of the invention is to provide a mechanism which is constructed and assembled with a view to insure that the insertion and passage of a slug is prevented in a number of different ways and which is therefore much less prone to successful tampering than conventional mechanisms.

An additional object of the invention is to provide a safety mechanism which, even though ideally suited for use in parking meters, is just as suited for use in nearly all other types of coin-operated machines including machines which sell time, services or commodities.

A feature of the invention resides in the provision of a safety mechanism for normally sealing coin insertion apertures (e.g., slots) in parking meters or other types of coin-operated machines. The mechanism comprises a frame or mask defining an aperture for insertion and passage of satisfactory coins (this term is intended to embrace preferably round coins in the form of legal tenders as well as prefabricated tokens which are specifically designed for use in the coin-operated machines embodying the improved safety mechanism) having a predetermined size and shape, a plurality of blocking or obstructing members in the form of vanes or the like which are movable with respect to the frame and with respect to each other between operative positions in which the blocking members overlie the apertures to thus prevent the insertion of coins or the like and inoperative positions in which the aperture is at least partially exposed (the blocking members may resemble the blades of shears or tongs and are preferably but not necessarily pivotable between operative and inoperative positions), scanning means (preferably including a discrete scanning member for each blocking member) which normally assumes a first position in which it is located in front of the blocking members (as considered in the direction of insertion of coins) and extends into the path of movement of a satisfactory coin into the aperture, the scanning means being displaccable by a satisfactory coin with respect to the frame and with respect to the blocking members to assume a predetermined second position, means for moving the blocking members to inoperative positions in response to dis placement of the scanning means to second position (such moving means preferably constitute component parts of the scanning means), and means for locking the blocking members in the operative positions in re sponse to movement of the scanning means to first position (such locking means preferably constitute component parts of the scanning means).

The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The improved mechanism itself, however, both as to its construction and its mode of operation, together with additional features and advantages thereof, will be best understood upon perusal of the following detailed description of certain specific embodiments with reference to the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is an elevational view of the improved safety mechanism with the blocking members in positions they assume when the insertion of a coin into and its passage through the aperture is blocked;

FIG. 2 is a similar elevational view but showing the blocking members in their inoperative positions;

FIG. 3 is a sectional view as seen in the direction of arrows from the line III-Ill of FIG. 1, showing a coin in the process of being introduced into the aperture; and

FIG. 4 is a similar sectional view but showing the coin in the aperture.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The drawing illustrates a safety mechanism which can obstruct or seal an aperture or slot 6 for insertion of a preferably round coin or token 9, hereinafter called coin. The mechanism comprises a mask or frame 1, scanning means including two elongated mobile scanning members 2, 3 which are displaceable by a satisfactory coin 9, and two blocking members or vanes 4, 5 which normally seal the slot 6 but can be displaced by the scanning members 2, 3 in response to insertion of a coin.

The frame or mask 1 consists of a single piece of metallic or synthetic plastic material and is provided with a guide channel 7 (see particularly FIG. 2) having a size and shape which is dependent on the dimensions of the coin 9. The channel 7 is located above a horizontal guide member or platform 8 along which the coin 9 slides during movement toward and into the slot 6, see particularly FIG. 3. The mask 1 is further formed with two pairs of aligned upright guide slots 10, 11 and 12, 13 which are normal to the horizontal channel 7 and respectively receive portions of the scanning members 2, 3. The guide slots 11 and 13 are respectively located above the guide slots 10, 12 and are bounded in part by rearwardly extending lugs 14, 15 (see FIGS. 1 or 3) which constitute bent-over portions of the mask 1. The lugs 14, 15 provide auxiliary guide surfaces for the scanning members 2, 3 and reduce the likelihood of their tilting with respect to the mask 1. The lower portion of the mask 1 is formed with two substantially U- shaped pockets 16 and 17 which define sockets or spaces 18, 19 for the blocking portions 38, 39 of the vanes 5, 6. The width of the sockets 18, 19 slightly exceeds the thickness of the blocking portions 38, 39 of the vanes 4, 5; these blocking portions are received in the sockets 18, 19 at least when the vanes 4, 5 assume their operative or obstructing positions shown in FIGS. 1 and 3 whereby the vanes are held against lateral movement (forwardly or rearwardly, as viewed in FIG. 1) and are properly guided while they overlie the slot 6.

The pockets 16, 17 are mirror symmetrical to two discrete pivot members 20, 21 which pivotably support the upper end portions of the vanes 4, 5 so that the vanes are pivotable in planes which are normal to the plane of FIG. 3 or 4 and parallel to each other. A bentover projection or arm 22 of the mask 1 is located between the pivot members 20, 21 and supports a resilient element here shown as a torsion spring 23 which biases the scanning members 2, 3. To this end, the torsion spring 23 has a pair of end portions or legs 24, 25 which respectively bear against the scanning members 2, 3 and allow each of these members to move independently of the other member.

The mask 1 further comprises slightly offset lateral end portions 26, 27 which serve as component parts of a means for securing the safety mechanism in a parking meter or another coin-operated machine wherein the mechanism is being put to use. Such other machines may include shoe shining machines, driers, washers, food or beverage dispensers and many others. The housing of the machine in which the mechanism of the present invention is to be put to use is configurated in such a way that it can properly engage with the end portions 26, 27. For example, the end portions 26, 27 can fit into or properly engage with complementary portions of the inner housing or casing of a coinoperated parking meter or the like wherein the inner housing comprises means for guiding a coin which has been advanced into and beyond the slot 6. Bent-over lugs 28, 29 of the mask 1 can be provided with tapped or untapped holes for the passage of the shanks of screws, bolts or analogous fasteners which serve to separably but rigidly fix the mask to the inner housing. In the illustrated embodiment, the end portions 26, 27 and lugs 28, 29 constitute a composite means for centering the mask 1 and the parts carried thereby in the housing of a coin-operated machine.

The vanes 4, 5 can partially overlap each other not unlike the blades of shears in response to pivoting about the respective pivot members 20, 21 in directions to assume the operative positions shown in FIG. 1. The upper portions of the vanes 4, 5 are respectively provided with mating gear segments 30 and 31 which have a ratio of one-to-one and serve to synchronize the movements of the vanes in opposite directions. The gear segments 30, 31 are respectively coaxial with the pivot members 20, 21 and are located diametrically opposite two motion receiving portions or arms 32, 33 which respectively serve as means for moving the blocking portions 38, 39 of the vanes 4, 5 to inoperative or non-obstructing positions in response to appropriate displacement of the scanning members 2, 3 by a satisfactory coin 9. The vanes 4, 5 are biased to their operative positions by a helical spring 34 the two end convolutions of which are respectively anchored in retainers 35, 36 provided therefor on the vanes 4, S at a level below the gear segments 30, 31. The major parts of the blocking portions 38, 39 of the vanes 4, S are located in a common plane and the blocking portion 38 comprises an extension 37 which is parallel to the general plane of the vane 5 and can be bypassed by this vane when the vanes 4, 5 are pivoted by the spring 34 to move toward the operative positions shown in FIG. 1. The height of the extension 37 at least equals the width of the guide channel 7. The extension 37 overlies the relatively narrow gap between the adjacent edge faces 38', 39' of the blocking portions 38, 39 when the vanes 4, 5 assume the operative positions of FIG. 1. The blocking portions 38, 39 are of arcuate shape and their height, as viewed in FIGS. 1 or 2, exceeds the width of the guide channel 7. As stated above the lowermost parts of the blocking portions 38, 39 respectively extend into the sockets 18, 19 when the vanes 4, 5 assume the positions shown in FIGS. 1 or 3. The sockets l8 and 19 flank the respective ends of the guide channel 7.

The inner edge faces of the vanes 4, 5, (i.e., those edge faces which are nearer to each other) are provided with recesses or notches 40, 41 which receive locking bolts 42, 43 when the vanes 4, 5 assume their operative positions. Thus, the vanes 4, 5 are not only biased to their operative positions by the helical spring 34 but are also positively locked in such operative positions by discrete bolts 42, 43.

The vanes 4, 5 are disposed at one side, and the scanning members 2, 3 are disposed at the other side of the mask 1 (see particularly FIGS. 3 and 4). The scanning members 2, 3 constitute two elongated slides which are movable up and down at right angles to the plane in which a coin 9 is being introduced into the slot 6. Each of the scanning members 2, 3 comprises three scanning faces 44, 45, 46 which are located in different planes and can be contacted by a coin 9 while the latter moves along the platform 8 toward and into the slot 6. The plane of each scanning face 44 is inclined with respect to the plane of the coin 9 and platform 8 so that is subdivides a force, which is being applied to the coin 9 during insertion, into several components. One of these components is normal to the direction of movement (arrow 109) of the coin 9 and causes the respective scanning member 2 or 3 to move against the opposition of the spring 23 because the coin 9 cannot yield during movement along the upper side of the platform 8. The spring 23 allows the scanning members 2, 3 to move from the first positions shown in FIGS. 1 and 3 to an extent which is determined by the thickness of the coin 9 and by the effective length of the scanning faces 44.

The scanning faces 45 of the members 2, 3 are substantially parallel to the upper side of the platform 8 (Le, to the guide channel 7 and to a coin 9 on the platform 8). These faces scan the upper side of the coin 9 and maintain the scanning members 2, 3 in raised or second positions (FIGS. 2 and 4) as long as a coin 9 remains in the space between the scanning faces 45 and the platform 8.

The scanning faces 46 are substantially normal to the plane of the upper side of the platform 8 and make sharp edges with the scanning faces 45 (see FIGS. 3

and 4). The angle between a scanning face 45 and the respective scanning face 46 is preferably an acute angle of slightly less than Since a coin 9 is normally provided with minted depressions or recesses, the spring 23 is free to move the scanning members 2, 3 downwardly so that the scanning faces 46 enter such depressions and continue to abut against the upper side of the coin 9 on the platform 8. The legs 24, 25 of the torsion spring 23 allow the members 2, 3 to descent indepen' dently of each other and to bear against the surface in the bottom of the respective portion of the depression in the upper side of the coin 9 so that the latter is held against retraction from the guide channel 7, Le, against movement counter to the direction of movement into and through the slot 6.

The scanning members 2, 3 are respectively provided with pairs of projections or arms 47, 48 and 47', 48' which extend through the guide slots 10, 11 and 12, 13 of the mask 1 and serve as a means for guiding the respective scanning members during movement relative to the mask. Portions of the projections 47, 47 of the scanning members 2 and 3 respectively constitute the aforementioned locking bolts 42, 43. The projections 48, 48' resemble hooks (see FIG. 4) and cooperate with the motion receiving arms 32, 33 of the vanes 4, 5 so that the vanes are pivoted away from each other when the scanning members 2, 3 are lifted by a coin 9 on the platform 8. The distance between the locking edges of the projections 47, 47' (locking bolts 42, 43)

and the pivoting edges of the hook-shaped projections 48, 48 is selected in such a way that the locking bolts 42, 43 are retracted from the respective recesses or notches 40, 41 when the projections 48, 48 begin to pivot the vanes 4, 5 through the medium of the motion receiving arms 32, 33. Thus, the vanes 4, 5 are invariably unlocked before they begin to move away from the operative positions shown in FIG. 1. The feature that the vanes 4, 5 are provided with mating gear segments 30, 31 insures that a thief or another unauthorized person cannot pivot one of the vanes 4, 5 when the other vane is still locked by the respective bolt 42 or 43. This will be readily appreciated by considering that the vanes 4, 5 can leave the operative positions shown in FIG. 1 only when the bolts 42, 43 are withdrawn at the same time so that the vanes 4 can pivot because the vane 5 is free to pivot or vice versa; in all other instances, the mating gear segments 30, 31 oppose a movement of the vanes 4, 5 from their operative positions.

It is clear that the safety mechanism of the present invention can be provided with three or more vanes each of which can be locked by a discrete bolt or the like and is free to move to a retracted or inoperative position only when all other vanes are unlocked at the same time. Such mechanism can be used in areas which are often visited by thieves so that the insertion of unsatisfactory coins or the removal of coins from the mechanism must be prevented with an even higher degree of reliability. In such modified mechanisms, the additional vane or vanes need not cooperate with the vanes 4, 5 to normally obstruct the slot 6, Le, such additional vane or vanes may be provided for the sole purpose of being locked in the operative position(s) and of preventing a movement of the vanes 4, 5 to inoperative positions except when a satisfactory coin or token is inserted into the guide channel 7 and slot 6.

As shown in FIG. 1, the vanes 4, are locked in their operative positions when the recesses or notches 40, 41 respectively receive the locking bolts 42, 43 forming part of projections 47, 47' of the scanning members 2, 3. The bolts 42, 43 are urged into the respective recesses 40, 41 by the corresponding legs 24, 25 of the torsion spring 23. The scanning faces 44, 45 of both scanning members are then located at a predetermined distance from the upper side of the platform 8 below the guide channel 7. As shown in FIG. 3, such distance is relatively small and merely allows for introduction of a relatively thin object which thereby abuts against the front sides of the blocking portions 38, 39 of the vanes 4, 5. This cannot cause the vanes to leave their operative positions because they remain locked by the bolts 42, 43 of the scanning members 2 and 3.

The operation is as follows:

The safety mechanism is assumed to be mounted in a coin-operated machine, preferably in or on the inner housing of such machine so that the guide channel 7 registers with the coin-admitting opening of the inner housing. As shown in FIGS. 3 and 4, the thickness or depth of the safety mechanism (as considered at right angles to the plane of the mask 1) is relatively small so that the mechanism occupies little room in a parking meter or the like directly behind the coin-admitting opening of the housing. In many coin-operated machines, the housing in front of and around the coinadmitting opening is funnel-shaped so as to enable a person to readily detect the locus for insertion of coins and to facilitate the introduction of coins into the opening and through the opening into and through the slot 6.

When a user of the machine decides to insert a coin 9, the coin is first caused to pass through the aforementioned opening of the housing and thereupon slides along the upper side of the platform 8 on its way into engagement with the scanning faces 44 of the scanning members 2, 3 which members face the coin-admitting opening of the housing for the improved mechanism. As the coin 9 advances along the platform 8 (see the arrow 109 in FIG. 3), its front portion first engages the scanning faces 44 of the members 2, 3. In fact, the scanning faces 44 can be positioned in such a way that they are engaged by a coin 9 before the latter reaches the platform 8. Due to the fact that the coin 9 is round or substantially round, its front portion is automatically centered between the lower end portions of the scanning members 2, 3 so that both scanning faces 44 are engaged simultaneously or substantially simultaneously. The scanning faces 44 slide along the upper front edge portion of the coin 9 (see FIG. 3) and move the scanning members 2, 3 upwardly to the positions shown for the scanning member 3 of FIG. 4. It will be noted that the scanning members 2, 3 move (arrow 123 in FIG. 3) at right angles to the direction of insertion of the coin 9 (arrow 109). The scanning members 2, 3 are lifted'against the opposition of the torsion spring 23 before the front portion of the coin 9 reaches the plane of the mask 1. During the first stage of upward movement of the scanning members 2 and 3, the locking bolts 42, 43 are respectively withdrawn from the recesses 40, 41 of the vanes 4, 5. During the next-following stage of upward movement of the scanning members 2, 3, the projections 48, 48 of these members respectively pivot the vanes 4, 5 through the medium of motion receiving arms 32, 33 to such an extent that the slot 6 for insertion ofthe coin 9 is exposed and the coin can advance in and beyond the slot 6 to drop into the vending machine and to thereby initiate an operation, such as the displacement of the pointer in a parking meter or the starting of a motor in a washer or dryer. The coin 9 moves between the upper side of the platform 8 and the scanning faces 45 of the members 2, 3 and its peripheral surface can directly engage the edge faces 38', 39' of the blocking portions 38, 39 of the vanes 4, 5 (see FIG. 2). Such engagement between the coin 9 and edge faces 38', 39 causes an additional pivotal movement of vanes 4, 5 in opposite directions. The pivotal movement of vanes 4, 5 (the vane 4 pivots counterclockwise and the vane 5 pivots clockwise, as viewed in FIG. 2) is terminated when the distance between the edge faces 38', 39 in the region directly above the platform 8 equals the diameter of the coin 9.

As the coin 9 continues to slide forwardly, the scanning faces 45 of both scanning members 2, 3 descend onto the upper side of the coin and thereby oppose a retraction of the coin in a direction counter to that indicated by the arrow 109 of FIG. 3. As mentioned above, the coin is normally provided with depressions which receive the lowermost portions of the scanning members 2, 3 whereby the scanning members offer an even greater resistance to retraction of the coin. It will be recalled that each side of a coin is normally provided with a raised marginal portion which comes into engagement with the scanning members 2, 3, if the person manipulating the vending machine wishes to retract a partially inserted coin.

As the major portion of the coin 9 advances beyond the space between the edge faces 38', 39', the spring 34 is free to gradually pivot the vanes 4, 5 in directions to reduce the effective width of the slot 6 so that the maximum effective width of the slot 6 never exceeds the diameter of the inserted coin. Once the major part of the coin 9 has been inserted beyond the common plane of the edge faces 38' and 39', the spring 34 causes the vanes 4, 5 to assist a further inward movement of the coin. The spring 23 is free to return the scanning members 2, 3 to the first or lower end positions and to thereby reintroduce the locking bolts 42, 43 into the respective recesses 40, 41 as soon as the insertion of the coin 9 is completed, i.e., as soon as the edge faces 38, 39' reach the positions shown in FIG. 1. The locking bolts 42, 43 then respectively abut agains the blocking portions 38, 39 of the vanes 4, 5 and positively hold the vanes against movement to the inoperative positions of FIG. 2 unless the operator inserts a second coin 9 which is such that it can lift the scanning members 2, 3.

The scanning faces 46 of the members 2, 3 descend behind a properly inserted coin to further reduce the likelihood of its retraction from the slot 6.

An important advantage of the improved safety mechanism is that it comprises a relatively small number of simple parts and that its thickness, as considered in the direction of insertion of a coin 9 (arrow 109), is extremely small. This is attributed to the fact that the vanes 4, 5 are pivotable in a plane which is parallel to the plane of the mask 1, and that the scanning members 2, 3 are reciprocable in a plane which is also parallel to the plane of the mask. Another advantage of the safety mechanism is that all of its parts can be assembled on and with the mask 1 so that the mechanism constitutes a self-supporting unit which can be readily installed in the housing of a coin-operated machine.

The gear segments 30 and 31 insure that the vanes 4, can leave their operative positions only when both scanning members 2, 3 assume their second or raised positions. Thus, tampering with one of the scanning members 2, 3 does not enable a thief or vandal to force a slug or the like beyond the blocking members 4, 5 because these blocking members can move only in synchronism or not at all.

A coin or slug which is too thin will not reach the scanning forces 44 and will not lift the members 2, 3 to their second positions, or such a coin or slug will fail to lift the scanning members 2, 3 sufficiently to expel the locking bolts 42, 43 from the respective recesses. A slug whose thickness exceeds the thickness of a satisfactory coin will strike the scanning members 2, 3 at a level above the faces 44 and will fail to produce a force which can lift the scanning members to the positions shown in FIG. 2 or 4. A slug whose diameter or width exceeds the diameter of a satisfactory coin 9 will be unable to enter the channel 7. Also, a slug which is not as round as a satisfactory coin will fail to pivot the blocking portions 38, 39 so that the blocking members or vanes 4, 5 cannot move beyond their operative positions and do not permit the slug to enter the coinoperated machine proper. Ifa slug has caused the scanning members 2, 3 to rise to a certain extent but not all the way to their upper or second positions, the leading portion of the slug strikes against the front faces of the blocking portions 38, 39 and is unable to pivot the blocking members 4, 5 to the extent which is necessary to permit entry of the slug into the coin-operated machine.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features which fairly constitute essential characteristics of the generic and specific aspects of our contribution to the art and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the claims.

What is claimed as new and desired to be protected by' Letters Patent is set forth in the appended:

l. A mechanism for normally sealing coin insertion slots in parking meters or other types of coin operated machines, comprising a frame defining an aperture for insertion and passage of satisfactory coins having a predetermined shape and size; a plurality of blocking members moveable with respect to said frame and with respect to each other between operative positions in which said blocking members overlie said aperture to thus prevent the insertion of coins or the like, and inoperative positions in which said aperture is at least partially exposed; a single scanning member for each of said blocking members and normally assuming a first position in which said scanning member extends into the path of movement of a satisfactory coin into said aperture, each of said scanning members has at least one scanning face which is located in the path of movement of a satisfactory coin into and through said aperture while the respective scanning member assumes said first position thereof whereby the satisfactory coin acts upon the scanning face and moves the respective scanning member with respect to said frame to said second position; means on each scanning member for moving the respective blocking member to said inoperative position in response to movement of the scanning member to said second position; and means on each snanning member for locking the respective blocking member in response to movement of the scanning member to said first position.

2. A mechanism as defined in claim 1, wherein said aperture is a slot.

3. A mechanism as defined in claim 1, wherein said scanning members are reciprocable between said first and second positions.

4. A mechanism as defined in claim 1, wherein said scanning members are movable between said first and second positions independently of each other, and further comprising means for holding said blocking members against movement to said inoperative positions as long as at least one of said scanning members is in said first position thereof.

5. A mechanism as defined in claim 1, wherein said blocking members are movable beyond said inoperative positions by a satisfactory coin which has entered and is in the process of moving through said aperture.

6. A mechanism as defined in claim 1, wherein said frame includes a mask and said aperture isa slot provided in said mask, said mask further including means defining a guide channel for coins moving into said slot, said channel-defining means including a platform bounding one side of said channel and providing a sur face along which a satisfactory coin is insertable into said slot.

7. A mechanism as defined in claim 1, wherein said blocking members include two blocking members which are pivotable between said operative and inoperative positions and said frame has a first side and a second side, said blocking members being adjacent to one side of said frame and further comprising a discrete pivot provided on said frame for each of said blocking members.

8. A mechanism as defined in claim 7, wherein said blocking members are pivotable in planes which are at least substantially normal to the direction of insertion and passage of a satisfactory coin into and through said aperture.

9. A mechanism for normally sealing coil insertion slots in parking meters or other types of coin operated machines, comprising a frame defining an aperture for insertion and passage of satisfactory coins having a predetermined shape and size, said frame having a first and a second side; a plurality of blocking members comprising mating gears adjacent to one side of said frame and being pivoted in planes which are at least substantially normal to the direction of insertion and passage of the claim into and through said aperture, said blocking members being pivotable with respect to said frame and with respect to each other about discrete pivots provided on said frame for each blocking member between operative positions in which said blocking members overlie said aperture to thus prevent insertion of coins or the like, and inoperative positions in which said aperture is at least partially exposed; a single scanning member for each of said blocking and normally assuming a first position in which said scanning member extends into the path of movement of a satisfactory coin into said aperture, each scanning member being displaceable by a satisfactory coin with respect to said frame to a second position; means on each scanning member for moving the respective blocking member to said inoperative position in response to movement of the scanning member to said second position; and means on each scanning member for locking the respective blocking member in response to movement of the scanning to said first position.

10. A mechanism as defined in claim 9, wherein said gears are coaxial with the respective pivots and have a ratio of one-to-one so that the extent of pivotal movement of one of said two blocking members matches the extent of pivotal movement of the other of said blocking members.

11. A mechanism as defined in claim 1, further comprising means for biasing said blocking members to said operative positions.

12. A mechanism as defined in claim 11, wherein said blocking members include a first and a second blocking member and said means for biasing comprises a spring having portions connected to said first and second blocking members.

13. A mechanism as defined in claim 1, wherein said blocking members include a first and a second blocking member, said first and second blocking members being pivotable between said operative and inoperative positions and having blocking portions which are adjacent to each other and overlie said aperture in the operative positions of said first and second blocking members, one of said blocking portions having an extension which overlaps the other blocking portion in the operative positions ofsaid first and second blocking members.

14. A mechanism as defined in claim 13, wherein said blocking portions are located in a common plane, at least in the operative positions of said first and second blocking members, and are separated from each other by a gap in the operative positions of said first and second blocking members, said extension extending across said gap while said first and second blocking members dwell in said operative positions thereof.

15. A mechanism for normally sealing coin insertion slots in parking meters or other types of coin operated machines, comprising a frame defining an aperture for insertion and passage of satisfactory coins having a predetermined shape and size; a plurality of blocking members having recesses and being movable with respect to said frame and with respect to each other between operative positions in which said blocking members overlie said aperture to thus prevent the insertion of coins or the like, and inoperative positions in which said aperture is at least partially exposed; a single scanning member for each of said blocking members and normally assuming a first position in which said scanning member extends into the path of movement of a satisfactory coin into said aperture, each scanning member being displaceable by a satisfactory coin with respect to said frame to a second position; means on each scanning member for moving the respective blocking member to said inoperative position in response to movement of said scanning member to said second position; and means on each scanning member for locking the respective blocking member in response to movement of the scanning member to said first position, said means for locking comprising a discrete locking portion for each of said recesses received in the respective recesses in the first position of said scanning members.

16. A mechanism as defined in claim 15, further comprising means for biasing said locking portions into the respective recesses independently of each otherv 17. A mechanism as defined in claim 1, wherein said means for moving comprises a discrete moving portion rigid with each of said scanning members, said blocking members comprising motion receiving portions which are engaged and moved by the respective moving portions in response to movement of the corresponding scanning members to said second positions.

18. A mechanism as defined in claim 1, wherein said blocking members are pivotable between said operative and inoperative positions and said frame comprises pockets receiving portions of said blocking members at least while said blocking members dwell in said operative positions thereof.

19. A mechanism as defined in claim 18, wherein said pockets constitute integral parts of said frame and are adjacent to said aperture.

20. A mechanism as defined in claim 1, wherein said frame has guide slots, said scanning members including projections movably extending into said guide slots.

21. A mechanism as defined in claim 1, wherein said scanning members are elongated and reciprocable between said first and second positions.

22. A mechanism as defined in claim 21, wherein said scanning members include a first and a second scanning member, and further comprising resilient means mounted on said frame and arranged to bias said first and second scanning members to said first positions independently of each other.

23. A mechanism as defined in claim 22, wherein said resilient means comprises a torsion spring having first and second legs which respectively bear against the other ends of said first and second scanning members.

24. A mechanism as defined in claim 1, wherein each of said scanning members has a plurality of coin scanning faces located in mutually inclined planes.

25. A mechanism as defined in claim 1, wherein each of said scanning members has a scanning face which is inclined with respect to the direction of movement of a satisfactory coin into said aperture and against which a satisfactory coin acts during insertion into said aperture to thereby produce a force one component of which moves the respective scanning member from said first to said second position.

26. A mechanism for normally sealing coin insertion slots in parking meters or other types of coin operated machines, comprising a frame defining an aperture for insertion and passage of satisfactory coins having a predetermined shape and size; a plurality of blocking members moveable with respect to said frame and with respect to each other between operative positions in which said blocking members overlie said aperture to thus prevent the insertion of coins or the like, and inoperative positions in which said aperture is at least partially exposed; a single scanning member for each of said blocking members and normally assuming a first position in which said scanning member extends into the path of movement of a satisfactory coin into said aperture, each scanning member being displaceable by a satisfactory coin with respect to said frame to a second position, each scanning member having three coin scanning faces each of which is arranged to engage a different portion of a satisfactory coin during insertion and passage of such coin into and through said aperture; means on each scanning member for moving the l3 respective blocking member to said inoperative position in response to movement of the scanning member to said second posititon; and means on each scanning member for locking the respective blocking member in response to movement of the scanning member to said first position.

27. A mechanism for normally scaling coin insertion slots in parking meters or other types of coin operated machines, comprising a frame defining an aperture for insertion in passage of satisfactory coins having a predetermined shape and size; a plurality of blocking members moveable with respect to said frame and with respect to each other between operative positions in which said blocking members overlie said aperture to thus prevent the insertion of coins or the like, and inoperative positions in which said aperture is at least partially exposed; a single scanning member for each of said blocking members and normally assuming a first position in which said scanning member extends into the path of movement of a satisfactory coin into said aperture, each scanning member being displaceable by a satisfactory coin with respect to said frame to a second position; means on each scanning member for moving the respective blocking member to said inoperative position in response to movement of the scanning member to said second position; and means on each scanning member for locking the respective blocking member in the response to movement of the scanning member to said first position, said frame having a pair of guide slots for each of said scanning members and each of said scanning members having two projections extending into and moveable in the slots of the respective pair of guide slots, one projection of each of said scanning members forming part of said means from moving said blocking members and the other projection of each of said scanning members forming part of said means for locking said blocking members.

28. A mechanism for normally sealing coin insertion slots in parking meters or other types of coin operated machines, comprising a frame defining an aperture for insertion and passage of satisfactory coins having a predetermined shape and size; a plurality of blocking members moveable with respect to said frame and with respect to each other between operative positions in which said blocking members overlie said aperture to thus prevent the insertion of coins or the like, and inoperative positions in which said aperture is at least partially exposed; a plurality of scanning members, one for each of said blocking members and normally assuming a first position in which said scanning members extend into the path of movement of a satisfactory coin into said aperture, each scanning member being displace able by a satisfactory coin with respect to said frame to a second position, said scanning members having scanning faces which bear against one side of a satisfactory coin during insertion into and passage of such coin through said aperture whereby said one side of the satisfactory coin maintains said scanning members in said second position; means on each scanning member for moving the respective blocking member to said inoperative position in response to movement of the scanning member to said second position; and means on each scanning member for locking the respective blocking member in response to movement of the scanning member to said first position.

29. A mechanism as defined in claim 28, wherein said scanning faces are substantially parallel to the direction of insertion of a satisfactory coin into said aperture.

30. A mechanism for normally sealing coin insertion slots in parking meters or other types of coin operated machines, comprising afrarne defining an aperture for insertion and passa ge of satisfactory coins having a predetermined shape and size; a plurality of blocking members movable with respect to said frame and with respect to each other between operative positions in which said blocking members overlie said aperture to thus prevent the insertion of coins or the like, and inoperative positions in which said aperture is at least par tially exposed, said blocking members being movable in a first plane; a plurality of scanning members, one for each of said blocking members and normally assuming a first position in which said scanning members extend into the path of movement of a satisfactory coin into said aperture, each scanning member being displaceable by a satisfactory coin with respect to said frame to a second position, each of said scanning members being moveable in a second plane normal to said first plane; guide means for guiding said coins during their movement into said aperture along a third plane which is normal to said first and second plane; means on each scanning member for moving the respective blocking member to said inoperative position in response to movement of the scanning member to said second position; and means on each scanning member for locking the respective blocking member in response to movement of the scanning member to said first position.

31. A mechanism as defined in claim 28, wherein each of said scanning member's includes a further scanning face which makes an acute angle with the respective first mentioned scanning face and prevents withdrawal of a satisfactory coin via said aperture once the satisfactory coin has been inserted beyond said first mentioned scanning faces.

32. A mechanism as defined in claim 28 for use with coins of the type wherein said one side of a satisfactory coin is provided with at least one depression into which at least one of said scanning faces extends to thereby oppose the withdrawal of a partially inserted satisfactory coin from said aperture.

33. A mechanism as defined in claim 1, wherein said blocking members have portions which are located in the path of movement of a satisfactory coin through said aperture in the inoperative positions of said blocking members so that the advancing coin moves said blocking members beyond said inoperative positions, and further comprising means for biasing said blocking members against the advancing satisfactory coin in said aperture.

34. A mechanism as defined in claim I for use with substantially round coins, further comprising means for biasing said blocking members to said operative positions and against a satisfactory coin during passage of such coin through said aperture, and for thereby promoting the movement of a satisfactory coin through said aperture once the major portion of such coin has advanced beyond said blocking members.

35. A mechanism for normally sealing coin insertion slots in parking meters or other types of coin operated machines, comprising a frame defining an aperture for insertion and passage of satisfactory coins having a predetermined shape and size; a plurality of blocking members pivotable with respect to said frame and with aperture, each scanning member being displaceable by a satisfactory coin with respect to said frame to a second position; means on each scanning member for moving the respective blocking member to said-inoperative position in response to movement of the scanning member to said second position; and means on each scanning member for locking the respective blocking member in response to movement of each scanning member to said first position. 

1. A mechanism for normally sealing coin insertion slots in parking meters or other types of coin operated machines, comprising a frame defining an aperture for insertion and passage of satisfactory coins having a predetermined shape and size; a plurality of blocking members moveable with respect to said frame and with respect to each other between operative positions in which said blocking members overlie said aperture to thus prevent the insertion of coins or the like, and inoperative positions in which said aperture is at least partially exposed; a single scanning member for each of said blocking members and normally assuming a first position in which said scanning member extends into the path of movement of a satisfactory coin into said aperture, each of said scanning members has at least one scanning face which is located in the path of movement of a satisfactory coin into and through said aperture while the respective scanning member assumes said first position thereof whereby the satisfactory coin acts upon the scanning face and moves the respective scanning member with respect to said frame to said second position; means on each scanning member for moving the respective blocking member to said inoperative position in response to movement of the scanning member to said second position; and means on each snanning member for locking the respective blocking member in response to movement of the scanning member to said first position.
 2. A mechanism as defined in claim 1, wherein said aperture is a slot.
 3. A mechanism as defined in claim 1, wherein said scanning members are reciprocable between said first and second positions.
 4. A mechanism as defined in claim 1, wherein said scanning members are movable between said first and second positions independently of each other, and further comprising means for holding said blocking members against movement to said inoperative positions as long as at least one of said scanning members is in said first position thereof.
 5. A mechanism as defined in claim 1, wherein said blocking members are movable beyond said inoperative positions by a satisfactory coin which has entered and is in the process of moving through said aperture.
 6. A mechanism as defined in claim 1, wherein said frame includes a mask and said aperture is a slot provided in said mask, said mask further including means defining a guide channel for coins moving into said slot, said channel-defining means including a platform bounding one side of said channel and providing a surface along which a satisfactory coin is insertable into said slot.
 7. A mechanism as defined in claim 1, wherein said blocking members include two blocking members which are pivotable between said operative and inoperative positions and said frame has a first side and a second side, said blocking members being adjacent to one side of said frame and further comprising a discrete pivot provided on said frame for each of said blocking members.
 8. A mechanism as defined in claim 7, wherein said blocking members are pivotable in planes which are at least substantially normal to the direction of insertion and passage of a satisfactory coin into and through said aperture.
 9. A mechanism for normally sealing coil insertion slots in parking meters or other types of coin operated machines, comprising a frame defining an aperture for insertion and passage of satisfactory coins having a predetermined shape and size, said frame having a first and a second side; a plurality of blocking members comprising mating gears adjacent to one side of said frame and being pivoted in planes which are at least substantially normal to the direction of insertion and passage of the claim into and through said aperture, said blocking members being pivotable with respect to said frame and with respect to each other about discrete pivots provided on said frame for each blocking member between operative positions in which said blocking members overlie said aperture to thus prevent insertion of coins or the like, and inoperative positions in which said aperture is at least partially exposed; a single scanning member for each of said blocking and normally assuming a first position in which said scanning member extends into the path of movement of a satisfactory coin into said aperture, each scanning member being displaceable by a satisfactory coin with respect to said frame to a second position; means on each scanning member for moving the respective blocking member to said inoperative position in response to movement of the scanning member to said second position; and means on each scanning member for locking the respective blocking member in response to movement of the sCanning to said first position.
 10. A mechanism as defined in claim 9, wherein said gears are coaxial with the respective pivots and have a ratio of one-to-one so that the extent of pivotal movement of one of said two blocking members matches the extent of pivotal movement of the other of said blocking members.
 11. A mechanism as defined in claim 1, further comprising means for biasing said blocking members to said operative positions.
 12. A mechanism as defined in claim 11, wherein said blocking members include a first and a second blocking member and said means for biasing comprises a spring having portions connected to said first and second blocking members.
 13. A mechanism as defined in claim 1, wherein said blocking members include a first and a second blocking member, said first and second blocking members being pivotable between said operative and inoperative positions and having blocking portions which are adjacent to each other and overlie said aperture in the operative positions of said first and second blocking members, one of said blocking portions having an extension which overlaps the other blocking portion in the operative positions of said first and second blocking members.
 14. A mechanism as defined in claim 13, wherein said blocking portions are located in a common plane, at least in the operative positions of said first and second blocking members, and are separated from each other by a gap in the operative positions of said first and second blocking members, said extension extending across said gap while said first and second blocking members dwell in said operative positions thereof.
 15. A mechanism for normally sealing coin insertion slots in parking meters or other types of coin operated machines, comprising a frame defining an aperture for insertion and passage of satisfactory coins having a predetermined shape and size; a plurality of blocking members having recesses and being movable with respect to said frame and with respect to each other between operative positions in which said blocking members overlie said aperture to thus prevent the insertion of coins or the like, and inoperative positions in which said aperture is at least partially exposed; a single scanning member for each of said blocking members and normally assuming a first position in which said scanning member extends into the path of movement of a satisfactory coin into said aperture, each scanning member being displaceable by a satisfactory coin with respect to said frame to a second position; means on each scanning member for moving the respective blocking member to said inoperative position in response to movement of said scanning member to said second position; and means on each scanning member for locking the respective blocking member in response to movement of the scanning member to said first position, said means for locking comprising a discrete locking portion for each of said recesses received in the respective recesses in the first position of said scanning members.
 16. A mechanism as defined in claim 15, further comprising means for biasing said locking portions into the respective recesses independently of each other.
 17. A mechanism as defined in claim 1, wherein said means for moving comprises a discrete moving portion rigid with each of said scanning members, said blocking members comprising motion receiving portions which are engaged and moved by the respective moving portions in response to movement of the corresponding scanning members to said second positions.
 18. A mechanism as defined in claim 1, wherein said blocking members are pivotable between said operative and inoperative positions and said frame comprises pockets receiving portions of said blocking members at least while said blocking members dwell in said operative positions thereof.
 19. A mechanism as defined in claim 18, wherein said pockets constitute integral parts of said frame and are adjacent to said aperture.
 20. A mechanism as defined in claim 1, wherein said frame has guide slots, said scanning members including projections movably extending into said guide slots.
 21. A mechanism as defined in claim 1, wherein said scanning members are elongated and reciprocable between said first and second positions.
 22. A mechanism as defined in claim 21, wherein said scanning members include a first and a second scanning member, and further comprising resilient means mounted on said frame and arranged to bias said first and second scanning members to said first positions independently of each other.
 23. A mechanism as defined in claim 22, wherein said resilient means comprises a torsion spring having first and second legs which respectively bear against the other ends of said first and second scanning members.
 24. A mechanism as defined in claim 1, wherein each of said scanning members has a plurality of coin scanning faces located in mutually inclined planes.
 25. A mechanism as defined in claim 1, wherein each of said scanning members has a scanning face which is inclined with respect to the direction of movement of a satisfactory coin into said aperture and against which a satisfactory coin acts during insertion into said aperture to thereby produce a force one component of which moves the respective scanning member from said first to said second position.
 26. A mechanism for normally sealing coin insertion slots in parking meters or other types of coin operated machines, comprising a frame defining an aperture for insertion and passage of satisfactory coins having a predetermined shape and size; a plurality of blocking members moveable with respect to said frame and with respect to each other between operative positions in which said blocking members overlie said aperture to thus prevent the insertion of coins or the like, and inoperative positions in which said aperture is at least partially exposed; a single scanning member for each of said blocking members and normally assuming a first position in which said scanning member extends into the path of movement of a satisfactory coin into said aperture, each scanning member being displaceable by a satisfactory coin with respect to said frame to a second position, each scanning member having three coin scanning faces each of which is arranged to engage a different portion of a satisfactory coin during insertion and passage of such coin into and through said aperture; means on each scanning member for moving the respective blocking member to said inoperative position in response to movement of the scanning member to said second posititon; and means on each scanning member for locking the respective blocking member in response to movement of the scanning member to said first position.
 27. A mechanism for normally sealing coin insertion slots in parking meters or other types of coin operated machines, comprising a frame defining an aperture for insertion in passage of satisfactory coins having a predetermined shape and size; a plurality of blocking members moveable with respect to said frame and with respect to each other between operative positions in which said blocking members overlie said aperture to thus prevent the insertion of coins or the like, and inoperative positions in which said aperture is at least partially exposed; a single scanning member for each of said blocking members and normally assuming a first position in which said scanning member extends into the path of movement of a satisfactory coin into said aperture, each scanning member being displaceable by a satisfactory coin with respect to said frame to a second position; means on each scanning member for moving the respective blocking member to said inoperative position in response to movement of the scanning member to said second position; and means on each scanning member for locking the respective blocking member in the response to movement of the scanning member to said first position, said frame having a pair of guide slots for each of said scanning members And each of said scanning members having two projections extending into and moveable in the slots of the respective pair of guide slots, one projection of each of said scanning members forming part of said means from moving said blocking members and the other projection of each of said scanning members forming part of said means for locking said blocking members.
 28. A mechanism for normally sealing coin insertion slots in parking meters or other types of coin operated machines, comprising a frame defining an aperture for insertion and passage of satisfactory coins having a predetermined shape and size; a plurality of blocking members moveable with respect to said frame and with respect to each other between operative positions in which said blocking members overlie said aperture to thus prevent the insertion of coins or the like, and inoperative positions in which said aperture is at least partially exposed; a plurality of scanning members, one for each of said blocking members and normally assuming a first position in which said scanning members extend into the path of movement of a satisfactory coin into said aperture, each scanning member being displaceable by a satisfactory coin with respect to said frame to a second position, said scanning members having scanning faces which bear against one side of a satisfactory coin during insertion into and passage of such coin through said aperture whereby said one side of the satisfactory coin maintains said scanning members in said second position; means on each scanning member for moving the respective blocking member to said inoperative position in response to movement of the scanning member to said second position; and means on each scanning member for locking the respective blocking member in response to movement of the scanning member to said first position.
 29. A mechanism as defined in claim 28, wherein said scanning faces are substantially parallel to the direction of insertion of a satisfactory coin into said aperture.
 30. A mechanism for normally sealing coin insertion slots in parking meters or other types of coin operated machines, comprising a frame defining an aperture for insertion and passage of satisfactory coins having a predetermined shape and size; a plurality of blocking members movable with respect to said frame and with respect to each other between operative positions in which said blocking members overlie said aperture to thus prevent the insertion of coins or the like, and inoperative positions in which said aperture is at least partially exposed, said blocking members being movable in a first plane; a plurality of scanning members, one for each of said blocking members and normally assuming a first position in which said scanning members extend into the path of movement of a satisfactory coin into said aperture, each scanning member being displaceable by a satisfactory coin with respect to said frame to a second position, each of said scanning members being moveable in a second plane normal to said first plane; guide means for guiding said coins during their movement into said aperture along a third plane which is normal to said first and second plane; means on each scanning member for moving the respective blocking member to said inoperative position in response to movement of the scanning member to said second position; and means on each scanning member for locking the respective blocking member in response to movement of the scanning member to said first position.
 31. A mechanism as defined in claim 28, wherein each of said scanning members includes a further scanning face which makes an acute angle with the respective first mentioned scanning face and prevents withdrawal of a satisfactory coin via said aperture once the satisfactory coin has been inserted beyond said first mentioned scanning faces.
 32. A mechanism as defined in claim 28 for use with coins of the type wherein said one side of a satisfactory coin is provided with at least one depression into which at leasT one of said scanning faces extends to thereby oppose the withdrawal of a partially inserted satisfactory coin from said aperture.
 33. A mechanism as defined in claim 1, wherein said blocking members have portions which are located in the path of movement of a satisfactory coin through said aperture in the inoperative positions of said blocking members so that the advancing coin moves said blocking members beyond said inoperative positions, and further comprising means for biasing said blocking members against the advancing satisfactory coin in said aperture.
 34. A mechanism as defined in claim 1 for use with substantially round coins, further comprising means for biasing said blocking members to said operative positions and against a satisfactory coin during passage of such coin through said aperture, and for thereby promoting the movement of a satisfactory coin through said aperture once the major portion of such coin has advanced beyond said blocking members.
 35. A mechanism for normally sealing coin insertion slots in parking meters or other types of coin operated machines, comprising a frame defining an aperture for insertion and passage of satisfactory coins having a predetermined shape and size; a plurality of blocking members pivotable with respect to said frame and with respect to each other between operative positions in which said blocking members overlie said aperture to thus prevent the insertion of coins or the like, and inoperative positions in which said aperture is at least partially exposed, said blocking members being coupled to each other for simultaneous pivoting movement in opposite directions; a single scanning member for each of said blocking member and normally assuming a first position in which said scanning member extends into the path of movement of a satisfactory coin into said aperture, each scanning member being displaceable by a satisfactory coin with respect to said frame to a second position; means on each scanning member for moving the respective blocking member to said inoperative position in response to movement of the scanning member to said second position; and means on each scanning member for locking the respective blocking member in response to movement of each scanning member to said first position. 